Systemic Error in Radiology

2017 ◽  
Vol 209 (3) ◽  
pp. 629-639 ◽  
Author(s):  
Stephen Waite ◽  
Jinel Moore Scott ◽  
Alan Legasto ◽  
Srinivas Kolla ◽  
Brian Gale ◽  
...  
Keyword(s):  
Systemic Error

Conjectures and reputations: The composition and reception of James Bradley's paper on the aberration of light with some reference to a third unpublished version

2009 ◽  
Vol 43 (1) ◽  
pp. 19-48 ◽  
Author(s):  
JOHN FISHER
Keyword(s):  
Royal Society ◽  
Newtonian Theory ◽  
The Earth ◽  
Systemic Error ◽  
The Law ◽  
Set Up ◽  
Short Time ◽  
Jupiter’S Satellites

AbstractIn January 1729 a paper written by James Bradley was read at two meetings of the Royal Society. On a newly discovered motion of the fixed stars, later described as the theory of the aberration of light, it was to transform the science of astrometry. The paper appeared as a narrative of a programme of observation first begun at Kew and finalized at Wanstead, but it was, in reality, a careful reconstruction devised to enhance his reputation in response to a recognition that the programme was initially conducted in terms that were inimical to what he conceived to be his interest. The planned attempt to repeat Robert Hooke's celebrated experiment by James Pound, Samuel Molyneux and George Graham was set up at Molyneux's residence in Kew with James Bradley replacing Pound after his untimely and sudden demise. The unexpected and counterintuitive behaviour of the object star γ Draconis and the eradication of any suspicion of instrumental or systemic error led to the abandonment of the attempt to measure annual parallax and the initiation of new conjectures. An annual nutation was proposed but after the observation of a control star, 35 Camelopardalis, this conjecture was abandoned. Unknown to Bradley and Graham a premature approach was made by Molyneux to Newton claiming that the ‘nutation’ negated the whole of Newton's system. In the abandonment of the nutation yet another conjecture opposed to Newtonian theory was proposed and abandoned. Bradley determined to use his own instrument designed on different principles by Graham to observe the phenomenon in Wanstead. At Wanstead Bradley observed many stars to determine the parameters of the phenomenon. With the law of the motion described, Bradley proposed a hypothesis to explain it. Drawn from his earlier work on the ephemerides of Jupiter's satellites his hypothesis of the ‘new-discovered motion’ was quickly presented to the Royal Society as Bradley was working on a later and more definitive version of his paper. It is this later, third, unpublished version that is commonly referred to throughout this essay. It issued a challenge to ‘anti-Copernicans’ to offer an explanation of the observed phenomenon in geostatic terms. One such astronomer, Eustachio Manfredi, had examined the phenomenon of ‘aberrations’ in detail, the term being his. It was Bradley who first applied the term to the ‘new-discovered motion’ and within a short time ‘aberration’ was being applied by astronomers in the reduction of their observations. Annual aberration was widely accepted as evidence of the motion of the Earth. The paper enhanced Bradley's reputation and projected him into the forefront of European astronomers.

An Investigation on Human Vibration Analysis Using Image Processing Method

2005 ◽  
Author(s):  
Maryam Hoviattalab ◽  
Roya Narimani ◽  
Alireza Mirbagheri
Keyword(s):  
Image Processing ◽  
Vibration Analysis ◽  
Processing Method ◽  
The Body ◽  
Vibration Measurement ◽  
Noise Sensitivity ◽  
Research Fields ◽  
Systemic Error ◽  
Vibration Measuring ◽  
Lower Noise

Vibration measurement is an important tool in many research fields; there are several methods for measuring vibration of a system. In conventional methods accelerometers are fixed to the body, so there is a systemic error due to fixing an external object to the body surface that interferes with the true vibration of the body. We have proposed image processing as a new method to record and determine the frequency response of human body. This method provides vibration measuring without using contacting sensors. Moreover the main advantage is its lower noise sensitivity in comparison to accelerometers. Further more another important point is the fact that all devices used in our developed measurement system are usually available in the biomechanics laboratory where a Gait system is functioning. This gives the opportunity for such laboratory to add vibration measurement to its capabilities without much excessive costs.

Generation of Atmospheric Constants over Some Locations in West Africa: A Theoretical Aid for Measuring Instruments Design

2016 ◽  
Vol 27 ◽  
pp. 119-146 ◽  
Author(s):  
Moses E. Emetere ◽  
Marvel L. Akinyemi
Keyword(s):  
West Africa ◽  
Dispersion Model ◽  
Statistical Investigation ◽  
West African ◽  
Measuring Instruments ◽  
Atmospheric Conditions ◽  
The West ◽  
Retention Capacity ◽  
Measuring Devices ◽  
Systemic Error

The performance of AERONET or AMMA in West Africa over the past two decades had been successful but not without its challenges. These challenges had resulted in the loss of large volume of useful data. The frequent failures of ground measuring devices over West Africa have been linked to the manufacturer and christened 'manufacturer-error'. In this paper, it was proposed that the frequent failure of ground measuring devices is due to systemic-error. To address the systemic-error, we propose that the configuration of the constants-embedded in the compact flash of the measuring devices is not compatible with the atmospheric conditions of the West African climate. A statistical investigation was carried out on both the ground and satellite dataset to determine the aerosols retention capacity within the West African space. A dispersion model was developed to incorporate salient assumptions and parameters like the Unified number. Fourteen and thirteen years dataset were obtained from Multi-angle Imaging SpectroRadiometer (MISR) and AERONET respectively. Five locations were considered in this study; Ilorin-Nigeria, Ouagadougou-Burkina Faso, Lome-Togo, Conakry-Guinea and Niamey-Niger which are positioned on latitude 8.5 oN, 12.37 oN, 6.17 oN, 9.55 oN, 13.5 oN and longitude 4.53 oE, 1.53 oW, 1.35 oE, 13.67 oW, 2.12 oE respectively. It was observed that the same aerosols retention occurred in West Africa region between 2003 and 2005. Also, it was observed that the high aerosols retention over the locations portray danger to the life form, such as unbearable thermal comfort, increased heat flux, partial famine e.t.c. Hence, the proper documentation and execution of the correct atmospheric constants over locations of West Africa is a novel concept.

The Design and Realization of Intelligent Control System in Temperature and Humidity of Tea Intelligent Fixation

2013 ◽  
Vol 401-403 ◽  
pp. 1636-1640
Author(s):  
Jian Zhang ◽  
Yan Ting Lan ◽  
Yi Wan
Keyword(s):  
Control System ◽  
Intelligent Control ◽  
Detection System ◽  
High Reliability ◽  
Intelligent Control System ◽  
Control Rules ◽  
Temperature And Humidity ◽  
Systemic Error ◽  
Long Time ◽  
Point Detection

Aiming at the difficulty in control in tea fixation process, the intelligent control technology is adopted in the research which is for the core to the C8051F340 SCM and adopts the multi-point detection system to collect the temperature and humidity data. Besides, the data transmission with the epistemic machine can be realized by the I2C Bus, SPI and so on while the control rules and parameters of the controller can be intended. Thus it can be seen that the multi-parameter control of the temperature and humidity can be realized in tea green removing technology. The bunk watchdog circuit is adopted in hardware design to repair the systems bug automatically and safeguard the control system operate stably for a long time in this research. Additionally, the PID control algorithm is applied in software design to control systemic error less than 2%. Practical application indicates that this system is with simple structure, high reliability and good scalability, and it also can reduce the amount of labor and improve the teas quality.

scholarly journals Night admission is an independent risk factor for mortality in trauma patients - a systemic error approach

2015 ◽  
Vol 42 (4) ◽  
pp. 209-214 ◽  
Author(s):  
LEONARDO DE SOUZA BARBOSA ◽  
GEIBEL SANTOS REIS DOS JÚNIOR ◽  
RICARDO ZANTIEFF TOPOLSKI CHAVES ◽  
DAVI JORGE FONTOURA SOLLA ◽  
LEONARDO FERNANDES CANEDO ◽  
...  
Keyword(s):  
Electronic Medical Records ◽  
Medical Records ◽  
Night Shift ◽  
Risk Classification ◽  
Trauma Patients ◽  
Degree Of Contamination ◽  
Systemic Error ◽  
Observational Cohort ◽  
The Impact ◽  
Retrospective Observational Cohort Study

ABSTRACTObjective:to assess the impact of the shift inlet trauma patients, who underwent surgery, in-hospital mortality.Methods:a retrospective observational cohort study from November 2011 to March 2012, with data collected through electronic medical records. The following variables were statistically analyzed: age, gender, city of origin, marital status, admission to the risk classification (based on the Manchester Protocol), degree of contamination, time / admission round, admission day and hospital outcome.Results:during the study period, 563 patients injured victims underwent surgery, with a mean age of 35.5 years (± 20.7), 422 (75%) were male, with 276 (49.9%) received in the night shift and 205 (36.4%) on weekends. Patients admitted at night and on weekends had higher mortality [19 (6.9%) vs. 6 (2.2%), p=0.014, and 11 (5.4%) vs. 14 (3.9%), p=0.014, respectively]. In the multivariate analysis, independent predictors of mortality were the night admission (OR 3.15), the red risk classification (OR 4.87), and age (OR 1.17).Conclusion:the admission of night shift and weekend patients was associated with more severe and presented higher mortality rate. Admission to the night shift was an independent factor of surgical mortality in trauma patients, along with the red risk classification and age.

scholarly journals Method comparison of Particle Enhanced Immunoturbidimetry (PEIT) with High Performance Liquid Chromatography (HPLC) for glycated hemoglobin (HbA1c) analysis

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Shabnam Dildar ◽  
Sheharbano Imran ◽  
Farah Naz
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Coefficient Of Variation ◽  
High Performance ◽  
Evaluation Method ◽  
Total Error ◽  
Method Comparison ◽  
Systemic Error ◽  
Hplc Technique ◽  
The Difference

Abstract Background and objective High Performance Liquid Chromatography (HPLC) technique is considered as a gold standard for HbA1c analysis however all laboratories cannot adopt it due to certain limitations. Our aim was to compare Particle Enhanced Immunoturbidimetry (PEIT) method with High Performance Liquid Chromatography (HPLC) for HbA1c analysis. Method All blood samples were analyzed by HPLC assay on a Bio-Rad D-10 analyzer and PEIT on an Erba XL-200 analyzer. Precision studies were undertaken and Coefficient of Variation (%CV) calculated. Systemic Error (SE), Random Error (RE) and Total Error (TEcalc) were obtained. The Total Allowable Error (TEa) set by the National Glycohemoglobin Standardization Program (NGSP) for HbA1c is 6%.The acceptable evaluation method is where TEcalc is less than TEa. Results The Precision studies were satisfactory with Coefficient of Variation (%CV) being less than 4% for both techniques. Mean HbA1c levels were slightly higher from HPLC than PEIT 9.07 ± 2.23% and 8.93 ± 2.10% respectively, although the difference was minimal. RE was 1.41%, TEcalc was 1.55%, which was less than TEa set by the NGSP. Both methods strongly correlated with the correlation coefficient (r) 0.9716, p < 0.0001. Conclusion Our study showed HbA1c analysis by PEIT technique is precise, accurate, rapid and convenient and can be employed as an alternative to HPLC technique in countries where cost is a major problem for diagnosis and treatment.

scholarly journals Identifying epithelial borders in cholesteatoma surgery using narrow band imaging

2021 ◽  
Author(s):  
Adrianus H. A. Baazil ◽  
Maura C. Eggink ◽  
Maarten J. F. De Wolf ◽  
Fenna A. Ebbens ◽  
Frederik G. Dikkers ◽  
...  
Keyword(s):  
Narrow Band ◽  
Residual Disease ◽  
Narrow Band Imaging ◽  
Quantitative Difference ◽  
Subjective Assessment ◽  
Level Of Evidence ◽  
Tertiary Referral Center ◽  
Significant Difference ◽  
Systemic Error ◽  
Cholesteatoma Surgery

Abstract Purpose To quantify changes in the perceived epithelial border with narrow band imaging (NBI) and white light imaging (WLI) during cholesteatoma surgery and to objectify possible benefits of NBI in otology. Methods Perioperative digital endoscopic images were captured during combined approach tympanoplasty at our tertiary referral center using WLI and NBI (415 nm and 540 nm wavelengths). Sixteen otologic surgeon defined the epithelial borders within 16 identical WLI and NBI photos. Pixels of these selections were calculated to analyze the quantitative difference between WLI and NBI. A questionnaire also analyzed the qualitative differences. Results Sixteen otologic surgeons participated in the study. Stratified per photo, only two photos yielded a significant difference: less pixels were selected with NBI than WLI. A Bland–Altman plot showed no systemic error. Stratified per otologist, four participants selected significantly more pixels with WLI than with NBI. Overall, no significant difference between selected pixels was found. Sub-analyses of surgeons with more than 5 years of experience yielded no additional findings. Despite these results, 60% believed NBI could be advantageous in defining epithelial borders, of which 83% believed NBI could reduce the risk of residual disease. Conclusion There was no objective difference in the identification of epithelial borders with NBI compared to WLI in cholesteatoma surgery. Therefore, we do not expect the use of NBI to evidently decrease the risk of residual cholesteatoma. However, subjective assessment does suggest a possible benefit of lighting techniques in otology. Level of evidence 3.

Design of Metamaterials 340GHz Polarizing Converter

2014 ◽  
Vol 556-562 ◽  
pp. 217-221
Author(s):  
Chi Liu ◽  
Xue Tian Wang ◽  
Jun Deng
Keyword(s):  
High Frequency ◽  
Short Wave ◽  
Radar System ◽  
Anisotropic Property ◽  
Wave Radar ◽  
Systemic Error

Nowadays, with the development of the high frequency and short wave radar system, the facilities are becoming more and more precision. This paper shows a very important part of the 340GHz radar system, which is the design of polarizing converter in the transceiver isolation network. Because of the big limit in the systemic error of the quasi-optical polarizing converter which is based on the principle of orthogonal polarizing isolation, here we use the latest technology – Metamaterials, to design the polarizing converter depending on its anisotropic property. Finally we find that the result of the periodicity polarization in 340GHz is good.

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